A slide gate for controlling fluid flow having improved slide gate seals.
Conventional slide gates are employed to control fluid flow through a passageway or channel. Conventional slide gates typically provide a frame assembly which defines an opening through which fluid flows, a gate slidely mounted to the frame assembly, and a gate operating means for generating movement in the gate between an open position and a closed position for regulating fluid flow through the opening.
As to particular conventional slide gates, the frame assembly can be mounted to walls which define a passageway or channel through which the fluid flows such that substantially all of the fluid flows through the opening in the frame assembly. In this way, fluid flow through the opening of the gate can be regulated by the position of the gate within the frame assembly. Conventional slide gates and their sealing members are shown in U.S. Pat. Nos. 3,760,593; 4,028,896; 4,226,533; 4,848,962, 5,141,361 and 6,176,493.
Conventional slide gate seals provide a seal between the gate slidely mounted to the frame assembly. Typically, a horizontal frame member of the frame assembly supports a top seal in facing relation to a corresponding first face of the gate, a bottom horizontal frame member provides a bottom channel which supports within a bottom seal in facing relation to the bottom edge of the gate, and a pair of vertical frame members each provide a side channel which supports within a corresponding one of a pair of side seals each side seal having a pair of seal members disposed to contact opposing faces of the gate.
Conventional top seals may have a rectangular shape bounded by four sides adapted to provide a pair faces. All or a portion of the surface area of the pair of faces can be disposed in facing relation to contact a corresponding portion of the surface of the gate. To increase the tightness of the top seal the sealing face can be defaulted by forcible urging to press against the face of gate. However, these conventional top seals when engaged with the face of the gate have substantial frictional drag which must be overcome by a substantially greater lifting force in operation of the slide gate.
Additionally, conventional top seals may collect debris because of the width of the sides. The debris can be transferred between the sealing surface of the top seal and the corresponding surface of the gate during operation of the gate. The debris can abrade the surface of the top seal and the surface of the gate causing a leak path or reducing the life of the top seal.
Conventional side seals may comprise a plurality of parts which must be adjusted in relation to one another to urge the pair of seal members into sealed engagement against the opposed faces of the gate. Because conventional seals require adjustment of a plurality of parts to seal and do not seal by self conforming to the opposed faces of the gate, installation and maintenance costs of conventional side seals can be a substantial expense. Additionally, conventional side seals having a plurality of parts may also provide a corresponding plurality of leak paths between the parts. Moreover, the structure of conventional side seals may transfer the forces of seating and unseating head to the fasteners which maintain the spatial relation of the plurality of parts rather than the structure of the vertical frame members.
Conventional bottom seals can be disposed in fixed relation within the bottom channel of the bottom horizontal frame member by application of an amount bonding agent. However, over time the continued compression of the bottom seal by engagement with bottom edge of the gate, as well as action of chemical agents in the fluid that passes through the slide gate, can cause the bonding agent to release. The bottom seal may then become in part or in whole displaced from the bottom channel of the bottom horizontal frame member.
Additionally, conventional top seals terminate at each end face in substantially perpendicular butting engagement with the end face of a side seal member. As a result, deflection of the end face of the top seal occurs substantially parallel with the flow of fluid through the slide and deflection of the side seal member occurs substantially perpendicular to the flow of fluid through the slide gate resulting in separation of the abutted surfaces and production of a corresponding leak path.
The instant invention provides slide gate seals and a seal system which overcomes in whole or in part certain of the forgoing disadvantages of conventional slide gate seals.